When a Chao evolves, it turns into an adult Chao, it becomes either a Dark, Hero, or Neutral Chao, and it becomes a type of Chao (i.e. swim, run, power ect.). The type that the Chao will become depends on what attribute your Chao is best in, so if you want a run type Chao give it a lot of run type Chaos Drives and Animals. Chao evolve three hours after being hatched. After 5 "Chao Years," Chao will make another cocoon, it will either be pink or gray. Pink means the Chao will reincarnate, and gray means it will die.

This topic is highly confused, even I didn't know what the "2nd Evolution" was until I did some research. Basically, when a Chao evolves into an adult Chao it will be able to go through a second evolution, however it does not go into a cocoon. Still don't get it? Ok then, I will go over it again.... First, the Chao evolves into an adult (Thats its FIRST evolution) then around the age of 3-4 it goes through a second evolution. So, when the Chao is 3-4, start giving it lots of Animals and Chaos Drives. It will start to change again (remember it wont go into a cocoon) it will just start changing on its own (like a baby Chao changes color when it is given Animals).

When a Chao dies it's because the Chao was unhappy or sick. Chao can get sick but it is not very common. It's best to take the Chao to the doctor when it is. Chao are probably sick if they start coughing and sneezing. If you see a Chao in a grey cocoon (sad music will also play), and you want it to reincarnate, restart the game and do as much as you can to make the Chao happy. But if you can't go back enough time, then there is no way to save the Chao. If you see a pink cocoon, the Chao is reincarnating. When the cocoon fades, an egg will be there instead of the Chao. The egg will hatch into a baby of the Chao that reincarnated.